The present invention relates to resin compositions and methods of using such compositions in subterranean formations. More particularly, the present invention relates to curable, permeable resin compositions and methods of using such compositions, for example, to control particulate migration.
Hydrocarbon wells are often located in subterranean zones that contain unconsolidated particulates that may migrate out of the subterranean formation with the oil, gas, water, and/or other fluids produced by the wells. The presence of particulates, such as formation sand, in produced fluids is undesirable in that the particulates may abrade pumping and other producing equipment and reduce the fluid production capabilities of the producing zones. Unconsolidated subterranean zones include those that contain loose particulates, those wherein the bonded particulates have insufficient bond strength to withstand the forces produced by the production of fluids through the zones.
One method of controlling particulates in unconsolidated formations involves placing a filtration bed containing gravel near the well bore in order to present a physical barrier to the transport of unconsolidated formation fines with the production of hydrocarbons. Typically, such so-called “gravel packing operations” involve the pumping and placement of a quantity of a desired particulate into the unconsolidated formation in an area adjacent to a well bore. Such packs may be time consuming and expensive to install.
Another method used to control particulates in unconsolidated formations involves consolidating unconsolidated subterranean producing zones by applying a resin followed by a spacer fluid and then a catalyst. Such techniques, however, may be problematic when, for example, an insufficient amount of spacer fluid is used between the application of the resin and the application of the external catalyst. The resin may come into contact with the external catalyst in the well bore itself rather than in the unconsolidated subterranean producing zone, which may result in rapid polymerization, potentially damaging the formation by plugging the pore channels, halting pumping when the well bore is plugged with solid material, or resulting in a down hole explosion as a result of the exothermic heat generated by the polymerization. Also, using these conventional processes to treat long intervals of unconsolidated regions is not practical due to the difficulty in determining if the entire interval has been successfully treated with both the resin and the external catalyst.